Dr Dirk Babendreier and Dr Lakpo Koku Agboyi,
lead authors of the study published in Insects, considered more
sustainable approaches to managing FAW – other than relying on more
potentially-harmful pesticides – as part of an Integrated Pest
Management (IPM) plan for farmers to help protect their maize crops.

The researchers reported on field trials that tested the
effectiveness and associated cost benefits of using maltodextrin,
neem-based products, ash and soil, as well as the locally produced soap
alata samina – set against the control insecticide emamectin benzoate –
in the Upper West and Greater Accra regions of Ghana.

Dr Babendreier and Dr Agboyi, along with their colleagues including,
Dr Jerry Nboyine, Dr Michael Osae and Mr Patrick Beseh, working from
SARI, BNARI and PPRSD, respectively in Ghana found that significant
reduction of larval numbers of the FAW and crop damage, together with
increased yields, were mostly achieved by applying emamectin benzoate.

However, while high efficiency and cost benefit ratios were also
achieved with the two neem-based products, maltodextrin was only
efficient at one of the two sites with a clear dose-depending effect and
the higher dosage nearly as effective as emamectin benzoate. Due to the
relatively high product cost, the scientists say maltodextrin was
generally less cost efficient.

They add that ash and soil, as well as alata samina soap treatments,
at the dosages tested, were not efficient in reducing FAW larval numbers
and crop damage and as such were not beneficial in increasing maize
yields. In addition, SARI and BNARI which hosted the trials reported
that soil/ash are laborious to use in FAW control therefore only
practical in a very small/limited scale.

Dr Babendreier said, “There is a lack of research on innovative and
sustainable management approaches of FAW, including local methods used
by farmers in many parts of the world, despite wide agreement that there
is an urgent need for those.”

The scientists highlight that farm households often use highly
hazardous and/or banned products with generally no appropriate personal
protective equipment. Such over reliance on insecticides, they argue, is
highly problematic due to potential environmental and health risks as
well as the strong capability of the FAW to quickly develop resistance.

They add that numerous applications of insecticides are increasing
production costs and, in particular, the often-used broad-spectrum
products may disrupt current production systems of small holder farmers
which are often based on low inputs and a certain reliance on natural
biological control.

Dr Agboyi said, “The shift to applying exclusively pesticides is not in line with Integrated Pest Management approaches and is unsustainable in the long run. While we tested only a small number of potential products/local methods, of which unfortunately a few were not shown to be effective, we believe that more research would be needed to see if soil, sand or soaps could be more beneficial if used in other ways.”